Ok, ignoring the slightly boastful tone 'high end' stuff in your post, I think the problem you will have is that nurseries which are any good will already be full up with children who do regular days/ full weeks. Sounds like you would be better looking for nannies willing to do some extra babysitting (eg nannies of school age children who could look after your child during the day whilst their charges are elsewhere?)

The nursery my dc go to has hourly rates. Don't know how exclusive or high end it is but it costs an arm and a leg (and is v good -Asquith chain, bound to be one near you)

Not sure if you can do it on an as hoc basis though you'd have to check, and your dd may struggle settling in if she is just there for the odd couple of hours.

I think what I'd do if I were you is find a good (read expensive) day nursery near you which will satisfy the upmarket requirement and book her in say 2 full mornings a week on a regular basis which would be 2 or 3 hours so you can have some time and she can get used to a regular schedule. It is usually cheaper and easier to get a place if you book regular full morning ime, even if you don't use all the time.

The only other thing I have done for the odd hour is use the crèches at local leisure centres for an hour or two while I went to a gym or a class. This works wells but you have to stay on site and they are functional rather than high end. If you join a posh gym or health club they might be more high end?

You could try taking a half day place for two or three days a week (but you'd have to pay for that, year round, whether you used every session or not). Otherwise it would be crèches (normally found in say gyms - I doubt if they're available other than for gym users though).

You budget of up to £10ph looks on the low side for a central London nanny (though it would get you an unqualified sitter) especially if you are not offering regular work.

There is an 'exclusive' family members' club - including gym, toddler groups and creche in Parsons Green which might be worth taking a look at. I know it's not Notting Hill, but sounds like what you are after. Non members can use the crèche for up to 2 hours and they also have drop off toddler groups where staff will supervise your child at tumble tots / messy play type stuff.

Leaving aside all the comments about 'high end', I think that you may need to revise your thinking about childcare costs/arrangements in central London.

£10 per hour, net (so £10 plus tax, NI and ERNIC on top) is the standard rate for a nanny.

Babysitters might be a bit less.

A childminder would also be cheaper.

Some nurseries do register to do 'emergency' or 'ad hoc' are through sites such as 'emergency childcare', but this varies from nursery to nursery. The cost for this at the nursery I use is a whopping £16 per hour....

Spend the time with your child perhaps and pay someone £10 an hour to tidy your house? Since you have a nanny for 2 mornings a week you already have loads of time off to do things for yourself. I have no nanny and no nursery, we spend a tenner a week on a cleaner and get the rest of the jobs done in the evening when the baby is asleep (my partner does his fair share as he realises that I spend the daytime taking care of the baby)

I agree that as a FT mother it is nice to have a break from time to time in order to do things that are difficult with a baby in tow. If you have no family nearby or even in the same country, it can be hard to ever get a break during the day.